In this lesson, the students will be able to explain that when an existing cell creates a new cell, the existing cell needs to copy its DNA. The students will learn that DNA replication is initiated when a helicase enzyme unwinds the DNA into two individual strands by using their book to research specific questions. By using their book and watching a quick video, the students will learn that DNA Polymerase allows new nucleotides to bind to the two existing individual DNA strands, thus creating two DNA from one DNA. The students will act out the process of DNA replication and thus explain the roles of helicase and DNA Polymerase in DNA replication, as well as reinforce DNA base-pairing relationships from the previous lesson.
RI LS1-2: Students demonstrate an understanding of the molecular basis of heredity by describing DNA structure and relating the DNA sequence to the genetic code. National Science Education Standard
(Content Standard A; 9-12): All students should develop abilities necessary to do scientific inquiry and understandings about scientific inquiry.
(Content Standard C; 9-12): All students should develop an understanding of molecular basis of heredity. Rhode Island Beginning Teacher Standards 2
Teachers create Learning Experiences that reflect an understanding of central concepts and tools of inquiry of the disciplines they teach. Teachers use a variety of explanations and multiple representations of concepts, including analogies, metaphors, and demonstrations and illustrations that help students develop conceptual understanding
Opportunities to Learn:
Depth of Knowledge
Webb Level 1 - Recall of facts, terms, purposes
Webb Level 2 - Skill and concept (explain the relationship between fact and term)
Differential Instruction
In addition to the handout for homework, I will have the students answer two of three questions from the book that deal with problems with DNA replication. These questions allow the students to apply the information from the lesson into real world scenarios.
I will have a peer teacher (another teacher) that will help those students that are having a harder time to understand the function of DNA Polymerase and Helicase within DNA replication.
Through the lecture, video, engagement with peers, and acting out DNA replication, I will use the tactile, auditory and visual modalities of learning.
Prerequisite Knowledge
From last semester, the students will need to know that nail size increases through cell division
From the previous lesson, they will need to know the structure of DNA, building blocks, and appropriate base pairings of bases within DNA
From last semester, they will need to know the function of an enzyme by recalling the function of ATP synthatase in respiration
Accommodations and modifications:
There are three students who have illegible handwriting. They will have the ability to use a laptop to write their notes and complete homework.
There are three students who have trouble concentrating. These students will be moved to the front row; I will not have any wall posters on the front walls.
If the students were not able to incorporate all the answers to the questions into their notebook, I will have a photocopy of all the questions with answers on reserve.
Environment
The students sit at tables. There are four students per table facing the teacher. There are six tables.
The Smart board is at the front wall facing the students.
Materials
I will need a whiteboard.
I will need an online video about DNA replication that will engage students to research questions (video).
I will need the biology text book which will engage students to research questions
Objectives:
After the lesson, the students will be able to
Explain how DNA creates copies of itself (artefact- writing the process in their notebooks and acting out the process of DNA Replication)
Explain that the function of Helicase is to unwind DNA (artefact - writing the function in their notebooks and acting out the process of DNA Replication)
Explain that the function of DNA Polymerase is to add nucleotides to individual strands of DNA (artefact - by writing the function in their notebook and by acting out the process of DNA Replication)
Opening
1) As I am taking attendance, I will write the following on the board: Using your prior knowledge about nail growth, how do nails grow (Answer - New cells are formed from old cells).
2) I will inform the students orally that when an existing cell creates a new cell, the DNA in the existing cell needs to be copied and given to the new cell. Using your book, what is this process called? (Answer - DNA Replication). I will ask the students to copy this information into their notebooks.
3) Last time, you were able to explain to me the structure of DNA and its building blocks. Today you will be able to explain to me how DNA is copied during the production of new cells.
Engagement
Part 1
1) I will ask a student volunteer to go up to the white board.
2) As a way to access their prior knowledge from the last period, I will ask the students sitting down to guide the volunteer in drawing a DNA molecule and specifically labeling its three building blocks and specific nitrogen-containing bases. I will give the students the following graphic organizer, which focuses on base pairs in DNA.
Understanding base pairs in DNA will allow the students to understand the function of DNA polymerase in the engagement.
3) I will tell the students orally, in order for DNA to be replicated/copied, multiple enzymes need to come into the picture. I will then ask the students, last quarter we learned about the enzyme, ATP synthetase, in respiration. Based on its function in respiration, how would you describe the function of an enzyme? (Answer - it is a protein that helps produce a change in a reaction). The students can use their book to answer this question.
4) I had the following questions on the smart board using powerpoint
: Using your book, find out what is helicase, and how is it involved in DNA replication? (Answer- helicase is an enzyme that is responsible for unwinding DNA during replication). I will have a volunteer write this information on the white board so that students see the answer.
I will ask the students to write the questions on the board and corresponding answers in their notebook. I will let the students know that they can use their notebook on an upcoming quiz. In addition, I will also be collecting the notebooks during the second to last lesson of the unit. If a student has all of the questions with the right corresponding answers, the student will receive extra points on the upcoming test on nucleic acids.
Using the smart board, I will present the students with a picture of a DNA molecule being unwound by the helicase enzyme. (helicase)
5) I will tell the students that the first step in DNA replication is that the DNA molecule needs to unwind by separating the bases from its appropriate base pair. The enzyme that does this is called Helicase. The two strands within a DNA molecule separate forming individual strands, similar to when I unzip my jacket (I demonstrate unzipping my jacket to the students).
6) Now I draw two individual strands on the white board. I tell the students that two identical double-stranded DNA will form from these two individual stranded DNA. I asked the students orally: Using your book, find out what enzyme is responsible for converting the two individual strands into two double strands of DNA. (Answer - DNA Polymerase). I will have the students write the answer in their notebook.
Part 2
1) We are going to now watch a quick video (see Materials section above) on DNA replication. Using the smart board, I will have the following question on a powerpoint slide
: What is the function of DNA Polymerase during replication (Answer - DNA polymerase allows bases from new nucleotides to connect to bases in the existing individual strands of DNA, based on appropriate base-pairing relationships within DNA. These new nucleotides line up and form the second strand needed in DNA). I will ask the students to write the answer in their notebook as they watch the video. I will have a volunteer write the answer to the question on the white board so that everyone can see the answer.
2) I will reinforce the answer on the board and the information in the video by telling the students orally that, DNA Polymerase is like Santa. I will draw the following representation on the board so the students can see this process one more time. If DNA Polymerase sees that a nucleotide on the existing individual DNA strand has an adenine, it finds a nucleotide with a thymine for it to connect. If DNA Polymerase sees a nucleotide on the existing individual DNA strand with a thymine, it finds a nucleotide with an adenine for it to connect. DNA Polymerase does this until nucleotides in both existing individual strands of DNA have the appropriate complementary nucleotides connected to it based on appropriate base pairing. The result is two identical molecules of DNA, one for the existing cell and one for the new cell. Each DNA molecule contains one strand from the parent and one new strand.
Part 3
1) Similar to the previous lesson, I will split the students into two teams.
2) I will instruct the students that they will have a quarter of an hour to use the information they have collected from the their book, video, and lecture, to create DNA replication by acting it out.
3) I will instruct the teams to work together and designate roles within the teams (example: helicase, base, phosphate unit, etc)
4) I will expect both teams to be able to explain, through acting, how DNA copies itself using helicase and DNA polymerase.
5) As the teams are rehearsing DNA replication, I will ask students in each team if they have any questions about the role they have in DNA replication.
6) After rehearsing DNA replication, I will flip a penny to see which team will act first. The first team will act out DNA replication in the far corner of the class while the students in the other team will wait their turn by beginning the handout for homework.
7) As the students act out DNA replication, I will evaluate the students by asking each student in the team to state who they are, what are they connected to, and what is your function (if you are an enzyme) If a student has difficulty in explaining their role in replication, I will guide the student by asking appropriate questions based on the information from the book and the video.
Closure:
Based on the information from the video and their book I will ask a student to explain how DNA creates copies of itself
I will ask a student to explain the function of Helicase and DNA Polymerase in DNA Replication.
I will then refer to the handout (engagement part 3) for homework that outlines the steps in DNA replication. The handout will have a representation of a DNA molecule with base pairings. The students will be asked to explain how this DNA molecule copies itself.
I will collect this handout at the beginning of the next period.
Assessment:
Formative questions about DNA replication in the opening
Formative questions about Helicase and DNA Polymerase in the engagement
Completed answers to questions in their notebook (notebooks will be collected in the second to last lesson of the unit)
Act out DNA replication at the end of the period (rubric to be added in the near future)
Complete Handout for homework (handout and rubric to be added in the near future)
Lesson Title: Copying Information
Context of Lesson:
In this lesson, the students will be able to explain that when an existing cell creates a new cell, the existing cell needs to copy its DNA. The students will learn that DNA replication is initiated when a helicase enzyme unwinds the DNA into two individual strands by using their book to research specific questions. By using their book and watching a quick video, the students will learn that DNA Polymerase allows new nucleotides to bind to the two existing individual DNA strands, thus creating two DNA from one DNA. The students will act out the process of DNA replication and thus explain the roles of helicase and DNA Polymerase in DNA replication, as well as reinforce DNA base-pairing relationships from the previous lesson.
Standard
RI LS1-2: Students demonstrate an understanding of the molecular basis of heredity by describing DNA structure and relating the DNA sequence to the genetic code.National Science Education Standard
(Content Standard A; 9-12): All students should develop abilities necessary to do scientific inquiry and understandings about scientific inquiry.
(Content Standard C; 9-12): All students should develop an understanding of molecular basis of heredity.
Rhode Island Beginning Teacher Standards 2
Teachers create Learning Experiences that reflect an understanding of central concepts and tools of inquiry of the disciplines they teach. Teachers use a variety of explanations and multiple representations of concepts, including analogies, metaphors, and demonstrations and illustrations that help students develop conceptual understanding
Opportunities to Learn:
Depth of Knowledge
Differential Instruction
Prerequisite Knowledge
Accommodations and modifications:
Environment
Materials
Objectives:
After the lesson, the students will be able toOpening
1) As I am taking attendance, I will write the following on the board: Using your prior knowledge about nail growth, how do nails grow (Answer - New cells are formed from old cells).2) I will inform the students orally that when an existing cell creates a new cell, the DNA in the existing cell needs to be copied and given to the new cell. Using your book, what is this process called? (Answer - DNA Replication). I will ask the students to copy this information into their notebooks.
3) Last time, you were able to explain to me the structure of DNA and its building blocks. Today you will be able to explain to me how DNA is copied during the production of new cells.
Engagement
Part 1
1) I will ask a student volunteer to go up to the white board.2) As a way to access their prior knowledge from the last period, I will ask the students sitting down to guide the volunteer in drawing a DNA molecule and specifically labeling its three building blocks and specific nitrogen-containing bases. I will give the students the following graphic organizer, which focuses on base pairs in DNA.
3) I will tell the students orally, in order for DNA to be replicated/copied, multiple enzymes need to come into the picture. I will then ask the students, last quarter we learned about the enzyme, ATP synthetase, in respiration. Based on its function in respiration, how would you describe the function of an enzyme? (Answer - it is a protein that helps produce a change in a reaction). The students can use their book to answer this question.
4) I had the following questions on the smart board using powerpoint
I will ask the students to write the questions on the board and corresponding answers in their notebook. I will let the students know that they can use their notebook on an upcoming quiz. In addition, I will also be collecting the notebooks during the second to last lesson of the unit. If a student has all of the questions with the right corresponding answers, the student will receive extra points on the upcoming test on nucleic acids.
Using the smart board, I will present the students with a picture of a DNA molecule being unwound by the helicase enzyme. (helicase)
5) I will tell the students that the first step in DNA replication is that the DNA molecule needs to unwind by separating the bases from its appropriate base pair. The enzyme that does this is called Helicase. The two strands within a DNA molecule separate forming individual strands, similar to when I unzip my jacket (I demonstrate unzipping my jacket to the students).
6) Now I draw two individual strands on the white board. I tell the students that two identical double-stranded DNA will form from these two individual stranded DNA. I asked the students orally: Using your book, find out what enzyme is responsible for converting the two individual strands into two double strands of DNA. (Answer - DNA Polymerase). I will have the students write the answer in their notebook.
Part 2
1) We are going to now watch a quick video (see Materials section above) on DNA replication. Using the smart board, I will have the following question on a powerpoint slide2) I will reinforce the answer on the board and the information in the video by telling the students orally that, DNA Polymerase is like Santa. I will draw the following representation on the board so the students can see this process one more time. If DNA Polymerase sees that a nucleotide on the existing individual DNA strand has an adenine, it finds a nucleotide with a thymine for it to connect. If DNA Polymerase sees a nucleotide on the existing individual DNA strand with a thymine, it finds a nucleotide with an adenine for it to connect. DNA Polymerase does this until nucleotides in both existing individual strands of DNA have the appropriate complementary nucleotides connected to it based on appropriate base pairing. The result is two identical molecules of DNA, one for the existing cell and one for the new cell. Each DNA molecule contains one strand from the parent and one new strand.
Part 3
1) Similar to the previous lesson, I will split the students into two teams.2) I will instruct the students that they will have a quarter of an hour to use the information they have collected from the their book, video, and lecture, to create DNA replication by acting it out.
3) I will instruct the teams to work together and designate roles within the teams (example: helicase, base, phosphate unit, etc)
4) I will expect both teams to be able to explain, through acting, how DNA copies itself using helicase and DNA polymerase.
5) As the teams are rehearsing DNA replication, I will ask students in each team if they have any questions about the role they have in DNA replication.
6) After rehearsing DNA replication, I will flip a penny to see which team will act first. The first team will act out DNA replication in the far corner of the class while the students in the other team will wait their turn by beginning the handout for homework.
7) As the students act out DNA replication, I will evaluate the students by asking each student in the team to state who they are, what are they connected to, and what is your function (if you are an enzyme) If a student has difficulty in explaining their role in replication, I will guide the student by asking appropriate questions based on the information from the book and the video.
Closure:
Assessment: